So if Brownlee and Ward are right, we’re only about halfway done (not nearing the end). It may seem strange to talk about the loss of CO2 being the end of the world when we so often talk about the dangers of too much CO2. The half-lives of these materials are 1.25 billion, 4.5 billion, and 14 billion years respectively, so most of the original fuel has already been used up. No matter what else happens before then, this will be the end of life on Earth. Lights out: If by “end of the world” you mean “end of the universe”, then a good end of everything is the end of the age of stars.